Method of requesting allocation of uplink resources for extended real-time polling service in a wireless communication system

ABSTRACT

Provided is a device and method for scheduling uplink resources in a wireless communication system supporting VoIP. When its data rate is decreased, an MS notifies a BS of the rate decreased. When increasing its data rate, the MS requests resource allocation to the BS by transmitting a BR header or a CQICH codeword. Compared to the conventional ertPS in which the BS periodically allocates uplink resources to the MS irrespective of the state of the MS, the BS does not allocate uplink resources when the MS transitions form a talk-spurt period to a silence period. Therefore, resources consumption arising from unnecessary bandwidth allocation is reduced.

PRIORITY

This application claims priority under 35 U.S.C. § 119 to an applicationentitled “Method of Requesting Allocation of Uplink Resources forExtended Real-Time Polling Service in a Wireless Communication System”filed in the Korean Intellectual Property Office on Apr. 28, 2005 andassigned Serial No. 2005-35774, the contents of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an uplink scheduling methodin a wireless communication system, and in particular, to a method ofscheduling uplink resources for Extended Real-Time Polling Service(ertPS) supporting Voice over Internet Protocol (VoIP).

2. Description of the Related Art

A scheduling scheme is needed to efficiently use resources in a wirelesscommunication system which provides a variety of services with limitedresources. It is ideal that unnecessarily allocated resources arerapidly returned and re-allocated to necessary services. Also, it isnecessary to reduce the amount of information sent with wirelessresources and use the extra resources for other purposes.

Many uplink scheduling schemes have been proposed for VoIP. They includeUnsolicited Grant Service (UGS), Real-Time Polling Service (rtPS), andertPS.

In UGS, a fixed amount of uplink resources are allocated upon userrequest. Hence, a user transmits data with the allocated uplinkresources. rtPS allocates required resources in response to a periodicuplink resource allocation request from the user. The user transmitsdata with resources appropriately allocated according to the amount ofthe data.

FIG. 1 illustrates a conventional uplink resource scheduling for UGS.

Referring to FIG. 1, the status of a Mobile Station (MS) is divided intoa talk-spurt period and a silence period on the time axis. Thetalk-spurt period is an on-period with transmission of data packets fromthe MS, while the silence period is an off-period without anytransmission of data packet. The same resources are allocated to the MSduring both periods. In the illustrated case of FIG. 1, resourcessupporting a full rate, Rate 1 are constantly allocated.

However, the MS does not use all the allocated resources in transmittingdata. During silence periods 110 and 118, the MS uses only minimumresources required to maintain the service (e.g. Rate ⅛).

It occurs that only a fraction of the allocated resources are usedduring the talk-spurt period. In other words, the MS transmits datapackets using the whole or part of the resources during the talk-spurtperiod. For instance, the MS transmits data packets at Rate 1, that is,using the entire allocated resources during a talk-spurt period 112.Yet, it uses Rate ½ (i.e. half of the resources) during a talk-spurtperiod 114. As the amount of transmission data is further reduced, theMS transmits the data packets at Rate ¼ (i.e. ¼ of the resources) duringa talk-spurt period 116. During a silence period 118, the MS uses theminimum resources supporting the minimum rate, Rate ⅛.

As described above, the constantly allocated resources are not fullyutilized during the periods 114, 116 and 118. The existence of theresulting extra resources implies inefficient uplink scheduling.Therefore, uplink resources are wasted during the talk-spurt periods aswell as during the silence periods.

FIG. 2 illustrates a conventional uplink resource scheduling for rtPS.

Referring to FIG. 2, the status of an MS is divided into a talk-spurtperiod and a silence period on the time axis. The talk-spurt period isan on-period with transmission of data packets to be sent from the MS,while the silence period is an off-period without any transmission ofdata packet.

In rtPS, the MS requests uplink resource allocation to a base station(BS) in steps 212 to 236. The requested resources are decided based onthe amount of packet data to be transmitted from the MS. The BSallocates the requested uplink resources to the MS. The MS thentransmits the data packets using the allocated resources during periods210, 220 and 230.

In the illustrated case of FIG. 2, there are three talk-spurt periods210, 220 and 230 according to data rates. The MS transmits data at Rate1 during the first talk-spurt period 210, at Rate ½ during the secondtalk-spurt period 220, and at Rate ¼ during the third talk-spurt period230. Therefore, the MS uses different amounts of resources during theperiods. The talk-spurt periods change from 210 to 230 due to thedecrease of data rate.

More specifically, upon generation of data packets to be transmitted,the MS requests resource allocation in step 212. The BS then allocatesmaximum resources to support a maximum rate (e.g. Rate 1). The MStransmits the data packets at Rate 1 using the allocated resources. Thetransmission of data packets at Rate 1 is repeated during the talk-spurtperiod 210.

As the amount of transmission data is reduced, and thus the data rateneeds to be changed, the MS requests resource allocation supporting thedecreased data rate (e.g. Rate ½) in step 222. The MS then transmits thedata packets using allocated resources. The transmission of data packetsat Rate ½ is repeated during the talk-spurt period 220.

When the data rate is further decreased during the talk-spurt period230, the MS requests allocation of resources supporting the furtherdecreased data rate (e.g. Rate ¼) in step 232. The MS then transmitsdata packets at Rate ¼. The transmission of data packets at Rate ¼ isrepeated during the talk-spurt period 230.

After completing the data packet transmission, the MS operates using theminimum resources (e.g. Rate ⅛) during a silence period 240.

As noted from the above description, rtPS requires periodic polling(i.e. uplink resource request, steps 212 to 218, steps 222 to 226, andsteps 232 to 236). Even within a period requiring the same amount ofresources 210, 220 or 230, periodic polling takes place (in steps 214 to218, steps 224 and 226, or steps 234 and 236). The unnecessary pollingleads to a waste of uplink resources.

Since both UGS and rtPS allocate uplink resources periodically accordingto scheduling type irrespective of the real-time status of the MS,uplink scheduling cannot be performed efficiently, reflecting thetime-variant status of the MS.

Compared to UGS and real time Polling Service (rtPS), Extended-real timePolling Service (ertPS) allocates resources upon a MS request andenables transmission of data packets using the allocated resourceswithout polling until the resources are changed. The MS expects toreceive the same resources from the BS without any further polling inertPS.

When a data rate decrease is required, the MS transmits data packets atthe decreased data rate. Simultaneously, the MS notifies the BS of thechange of resources due to the decrease of the data rate. Therefore, theBS can use the extra resources saved from the MS for other purposes.

The MS uses the Extended PiggyBack Request (PBR) field of a GrantManagement subheader to notify the BS of the change of the data rate.The Grant Management subheader has the following configuration. TABLE 1Size Syntax (bits) Notes Grant Management Subheader { — —  if(scheduling service type==UGS) { — —   SI 1 —   PM 1 —   FLI 1 —   FL 4—   Reserved 9 Shall be set to zero   } else if (scheduling servicetype==Extended rtPS) { — —   Extended piggyback request 11  —   FLI 1 —  FL 4 —   } else { — —   Piggyback Request 16  —   } — — } — —

In Table 1, one Most Significant Bit (MSB) of Extended PBR is used as anindicator indicating the change of data rate. If the MSB is set to 1, itimplies that the data rate is changed. The remaining 10 LeastSignificant Bits (LSBs) of Extended PBR indicate the changed data rate.If the MSB is set to 0, it implies that the data rate is unchanged.

Alternatively, the MS can request allocation of a bandwidthcorresponding to a requested data rate by the Bandwidth Request (BR)field of a BR and Uplink (UL) transmit power report header which isformatted as follows. TABLE 2 HT = 1 EC = 0 Type (3) = BR (11) (1) (1)0b011 UL TX Power (8) CID MSB (8) CID LSB (8) HCS (8)

Referring to Table 2, one MSB of BR is used as an indicator indicatingthe change of data rate. If the MSB is set to 1, it implies that thedata rate is changed. The 10 LSBs of BR indicate the changed data rate.If the MSB is set to 0, it implies that BR and UL transmit power reportheader is a typical header requesting a bandwidth for resourceallocation.

FIG. 3 illustrates a conventional uplink scheduling for ertPS.

Referring to FIG. 3, the status of an MS is divided into a talk-spurtperiod and a silence period on the time axis. The talk-spurt period isan on-period with transmission of data packets to be sent from the MS,while the silence period is an off-period without any transmission ofdata packet.

When transitioning from the silence period to the talk-spurt period, theMS requests resource allocation to the BS by a BR header in step 310.Table 2 above showing the bandwidth request and uplink transmit powerreport header is an example of the BR header. The BR header carriesbandwidth request information requesting allocation of the sameresources without any further polling.

Upon receipt of the BR header, the BS allocates resources correspondingto a maximum data rate periodically to the MS during the talk-spurtperiod 312. The MS transmits data at the maximum data rate.

When the data rate is to be changed, the MS transmits data at thechanged data rate during the next talk-spurt period. The changed datarate is lower than the previous data rate. In the illustrated case Rate1 decreases to Rate ½. Meanwhile, the MS notifies the BS of the changeof data rate by a Grant Management subheader. Then the MS transmits dataat the changed data rate periodically during the talk-spurt period 314.

Upon receipt of the Grant Management subheader, the BS allocates asminimum resources as supporting Rate ½. The BS then allocates the extraresources saved from the MS for other purposes.

If the data rate is further to be decreased during data transmission atRate ½, the MS transmits data at Rate ¼ during the next talk-spurtperiod 316. Meanwhile, the MS notifies the BS of the change of data rateby a Grant Management subheader. Then the MS transmits data at thechanged data rate periodically during the talk-spurt period 316. The BSallocates as minimum resources as supporting Rate ¼.

If the data rate is further to be decreased during data transmission atRate ¼, the MS changes the data rate to Rate ⅛ for the next talk-spurtperiod. Meanwhile, the MS notifies the BS of the change of data rate bya Grant Management subheader. The BS then allocates as minimum resourcesas supporting Rate ⅛.

As described above, when the data rate decreases, the MS transmitsinformation about the changed data rate to the BS by the GrantManagement subheader, and the BS allocates resources to the MS accordingto the changed data rate.

However, it may occur that the MS wants to increase the decreased datarate during the talk-spurt period. In order to transmit uplink data atthe increased data rate, the MS needs as much as possible uplinkresources. However, there is no specified method for notifying the BS ofthe intention of the MS regarding the increase of the data rate.Accordingly, there exists a need for a method of increasing a decreaseddata rate in an MS during a talk-spurt period.

Conventionally, the BS periodically allocates resources supporting theminimum data rate to the MS during the silence period, and the MS, whentransitioning from the silence period to the talk-spurt period, requestsa bandwidth using the minimum resources. During the silence period,hence, the BS periodically allocates the MS uplink resources supportingtransmission of a 6-byte BR header or uplink resources supportingtransmission of a BR subheader in the form of a piggy back request asillustrated in Table 1, that is, a 6-byte Generic Medium Access Control(MAC) header and a 2-byte Grant Management subheader. While theseminimum resources are needed for the MS to request a bandwidth fortransitioning from the silence period to the talk-spurt period, theperiodic resource allocation may not be needed because the MS does notknow when to transition to the talk-spurt period.

SUMMARY OF THE INVENTION

An object of the present invention is to substantially solve at leastthe above problems and/or disadvantages and to provide at least theadvantages below. Accordingly, the present invention provides a methodof requesting resource allocation to a BS when an MS is to increase datarate for ertPS in a wireless communication system.

The present invention provides a method of efficiently using uplinkresources by saving uplink resources from an MS which is in a silenceperiod due to the absence of transmission data in ertPS.

According to one aspect of the present invention, in a method ofrequesting allocation of wireless resources in an MS in a wirelesscommunication system, the MS determines whether a current data rate isto be increased. If the rate increase is needed, the MS requestsallocation of an uplink bandwidth for the rate increase to a BS. The MSis then allocated an increased bandwidth from the BS in correspondencewith the bandwidth allocation request.

According to another aspect of the present invention, in a method ofallocating wireless resources in a BS in a wireless communicationsystem, the BS receives a bandwidth allocation request for a rateincrease from the MS, and allocates a bandwidth in correspondence withthe bandwidth allocation request to the MS.

According to a further aspect of the present invention, in an apparatusfor requesting allocation of wireless resources in a wirelesscommunication system, a MS determines whether a current data rate is tobe increased, requests allocation of an uplink bandwidth for the rateincrease to a BS, if the rate increase is needed, and is allocated anincreased bandwidth from the BS in correspondence with the bandwidthallocation request.

According to still another aspect of the present invention, in anapparatus for allocating wireless resources in a wireless communicationsystem, a BS receives a bandwidth allocation request for a rate increasefrom the MS, and allocates a bandwidth in correspondence with thebandwidth allocation request to the MS.

According to yet another aspect of the present invention, in a method ofrequesting allocation of uplink resources for ertPS in a MS in awireless communication system, the MS requests allocation of anincreased bandwidth by transmitting a CQICH codeword to a BS, whendetermining that an uplink bandwidth allocation is required, and isallocated a bandwidth supporting a maximum rate from the BS.

According to yet further aspect of the present invention, in a method ofallocating uplink resources for ertPS in a BS in a wirelesscommunication system, the BS receives a CQICH codeword requestingallocation of an increased bandwidth from a MS, and allocates abandwidth supporting a maximum rate to the MS.

According to still another further aspect of the present invention, inan apparatus for requesting allocation of uplink resources for ertPS ina wireless communication system, a MS requests allocation of anincreased bandwidth by transmitting a CQICH codeword to a BS, whendetermining that an uplink bandwidth allocation is required, and isallocated a bandwidth supporting a maximum rate from the BS.

According to further another aspect of the present invention, in anapparatus for allocating uplink resources for ertPS in a wirelesscommunication system, a BS receives a CQICH codeword requestingallocation of an increased bandwidth from a MS, and allocates abandwidth supporting a maximum rate to the MS.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 illustrates a conventional uplink scheduling for UGS;

FIG. 2 illustrates a conventional uplink scheduling for rtPS;

FIG. 3 illustrates a conventional uplink scheduling for ertPS;

FIGS. 4 and 5 are flowcharts diagram illustrating an operation foruplink scheduling for ertPS in an MS according to the present invention;

FIG. 6 is a flowchart diagram illustrating an operation for uplinkscheduling for ertPS in a BS according to the present invention; and

FIG. 7 is a diagram illustrating a signal flow between the MS and the BSfor uplink scheduling in ertPS according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described hereinbelow with reference to the accompanying drawings. In the followingdescription, well-known functions or constructions are not described indetail since they would obscure the invention in unnecessary detail.

The present invention provides a method of increasing the data rate ofan Mobile Station (MS) in Extended-real time Polling Service (ertPS)uplink scheduling. It is assumed that the MS is transmitting datapackets at a lower rate than a maximum rate. For this purpose, a methodof transmitting rate increase information requesting a rate increase toa BS (Base Station) by the MS is provided.

Conventionally, when the data rate is equivalent to no datatransmission, minimum resources supporting a minimum rate areperiodically allocated. In contrast, resources are allocated only uponrequest of the MS in the present invention.

Regarding uplink scheduling according to the present invention, theoperations of the MS and the BS will be separately described below.

A. MS Operation

FIGS. 4 and 5 are flowchart diagrams illustrating an operation foruplink scheduling for ertPS in the MS according to the presentinvention. Specifically, FIG. 4 is a flowchart diagram illustrating anMS operation when the MS is not transmitting data and FIG. 5 is aflowchart diagram illustrating an MS operation when the MS istransmitting data.

Referring to FIG. 4, the MS monitors the presence or absence oftransmission data in step 410. In the absence of transmission data, theMS is kept in an off state. In the presence of transmission data, the MSrequests bandwidth allocation in step 412. The present invention isbased on the premise that resources are not allocated to the MS in aninitial state, i.e. in an off state. Therefore, a novel technique mustbe developed for the MS in the off state to request bandwidthallocation, which will be described later in detail.

In step 414, the MS is allocated a bandwidth from the BS. The bandwidthis one requested by the MS or a bandwidth supporting a predeterminedmaximum rate. In the present invention, the latter case is assumed. TheMS starts data transmission at a data rate corresponding to thebandwidth in step 416.

The MS, which has initiated the data transmission in the procedure ofFIG. 4, continues its operation in an on state according to theprocedure of FIG. 5.

Referring to FIG. 5, the MS transmits data at the data ratecorresponding to the bandwidth in step 510. During the datatransmission, the MS determines whether the data rate needs to bechanged (i.e. increase or decrease in steps 512 and 520). If neither arate increase nor a rate decrease is required, the MS continues datatransmission at the current data rate in step 510.

However, if a rate decrease is required, the MS requests a rate decreasein step 514. The MS determines whether the requested data rate is aminimum rate in step 516.

In case of the minimum rate, the MS transitions to the off state,considering that the allocated bandwidth has been released in step 518because resources are not allocated to the MS in an off-state in thepresent invention. The MS then operates in the procedure of FIG. 4.

The minimum rate is a data rate that does not affect the quality ofcommunication even though the MS transmits no data. In general, theminimum rate is Rate ⅛ or lower. In this case, the MS sets the MSB ofthe Extended PiggyBack Request (PBR) field of the Grant Managementsubheader to 1 and sets the 10 LSBs to Rate ⅛ or lower in order torequest a rate decrease. Consequently, the BS does not need to allocatea bandwidth to the following frames any more.

If the requested rate is not the minimum rate, the MS is allocated areduced bandwidth in step 524. The MS then continues data transmissionat a data rate corresponding to the allocated bandwidth in step 510.

On the other hand, if a rate increase is required, the MS requests arate increase in step 522. For the rate increase, an extra bandwidthmust be available. Therefore, the present invention provides a method ofallocating an additional bandwidth for a rate increase request, whichwill be described later in detail.

In step 524, the MS is allocated an increased bandwidth. The MS thenreturns to step 510 in which it continues data transmission at a datarate corresponding to the allocated bandwidth.

The bandwidth allocation request step 412 and the rate increase requeststep 522 will be described in detail below.

Requesting a bandwidth allocation and a rate increase can be consideredin two ways: by a general bandwidth request (BR) header or by a codewordover a Channel Quality Information CHannel (CQICH) (i.e. CQICHcodeword). The rate increase request is applied when a lower rate than amaximum rate negotiated during an initial service setup is used.

Regarding the use of the bandwidth request header, for example, the MScan use the BR field and UL transmit power report header as thebandwidth request header. Besides, the MS can use any header that cancarry a bandwidth request, such as a PBR. Meanwhile, when increasing adata rate, the MS transmits a bandwidth request header containing arequested bandwidth. The BS then allocates uplink resourcescorresponding to the requested bandwidth to the MS. For example, the BSallocates a predetermined maximum bandwidth in case of a bandwidthallocation request or the requested bandwidth in case of a rate increaserequest.

To transmit the bandwidth request header, the MS needs to be allocateduplink resources. Thus, the MS transmits a bandwidth request code torequest allocation of uplink resources for transmission of the bandwidthrequest header.

The MS can transmit the bandwidth request code in an uplink slotallocated for use in requesting a bandwidth (bandwidth request slot).The uplink bandwidth request slot is a slot used for ranging in anexisting wireless network. Hence, the uplink bandwidth request slot isavailable without allocation of additional resources. L of 255 codes arepre-defined as bandwidth request codes for allocation of uplinkresources. L is the positive integer.

The MS selects one of the L bandwidth request codes and transmits theselected bandwidth request code in the bandwidth request slot. Thebandwidth request then allocates uplink resources required fortransmission of the bandwidth request header.

As described above, the MS requests uplink resources for transmission ofa bandwidth request header by transmitting a bandwidth request code. TheMS can transmit the bandwidth request header using resources allocatedby the BS. The bandwidth request field of the bandwidth request headercontains information about uplink resources supporting a requested datarate.

Regarding transmission of a CQICH codeword, the MS generally deliversfeedback information or anchor BS switching information in a Fast BaseStation Switching (FBSS) operation on the CQICH. For each operation, aCQICH codeword is predetermined. Hence, the MS transmits a CQICHcodeword corresponding to an intended operation on the CQICH channel. Inaccordance with the present invention, one of predetermined CQICHcodewords is used to increase a decreased data rate or request bandwidthallocation in an off state, for ertPS. The MS, which supports ertPS,transmits a CQICH codeword predetermined for using a high data rate or aCQICH codeword predetermined for bandwidth allocation on the CQICH. Thetransmitted CQICH codeword is pre-defined to request uplink resources tothe BS.

Upon receipt of the CQICH codeword, the BS recognizes that the MSrequests a rate increase or bandwidth allocation. The BS then allocatesuplink resources supporting the maximum rate or uplink resourcessupporting a requested rate increase to the MS. The maximum rate isdetermined by an initial service negotiation procedure between the MSand the BS.

B. BS Operation

FIG. 6 is a flowchart diagram illustrating an operation for uplinkscheduling for ertPS in the BS according to the present invention.

Referring to FIG. 6, the BS monitors reception of a bandwidth allocationrequest from the MS in an off state in step 610. The bandwidthallocation is requested by a bandwidth request header, a bandwidthrequest code or a CQICH codeword from the MS.

Upon receipt of the bandwidth allocation request, the BS allocates arequested bandwidth by the MS or a bandwidth supporting a maximum ratedecided during an initial service negotiation with the MS in step 612and receives data from the MS at a rate corresponding to the allocatedbandwidth.

In step 616, the BS determines whether a Grant Management subheaderrequesting a decrease of the current bandwidth is piggybacked in thereceived data. In the absence of the bandwidth decrease request, the BSmonitors reception of a rate increase request in step 622.

In the absence of the rate increase request, the BS receives data byre-allocating the current bandwidth in step 614, considering that thereis no change in the data rate of the MS.

On the contrary, upon receipt of the rate increase request, the BSallocates the requested bandwidth in step 620. If the rate increaserequest does not provide information about the requested data rate, theBS can allocate the bandwidth supporting the maximum rate. The rateincrease request is also made by one of a bandwidth request header, abandwidth request code and a CQICH codeword.

If receiving the Grant Management subheader including rate changeinformation (i.e. the rate decrease request) in step 616, the BSdetermines whether the requested rate is a minimum rate in step 618. Theminimum rate is a non-zero data rate that does not affect communicationquality even though the MS transmits no data.

If the requested rate is not the minimum rate, the BS allocates abandwidth based on the data rate set in the Grant Management subheaderin step 620. In step 614, the BS receives data using the newly allocatedbandwidth.

In case of the minimum rate, the BS determines that the MS will nottransmit any more data. Thus, the BS determines whether the MS requestsbandwidth allocation, without allocating any further bandwidth, in step610. Also, when the 10 LSBs of the Extended PBR of the Grant Managementsubheader are 0, the BS does not allocate a bandwidth from the nextframe on.

C. Signaling

FIG. 7 is a diagram illustrating a signal flow between the MS and the BSfor uplink scheduling in ertPS according to the present invention.

Referring to FIG. 7, an MS 740 has no data to transmit to a BS 750 andthus stays in an off period in step 701. Upon generation of transmissiondata in step 703, the MS 740 transmits to the BS 750 a codewordrequesting bandwidth allocation for data transmission on a CQICH in step705. In step 707, the BS 750 determines that the MS 740 needs uplinkresources supporting a maximum rate. The BS then allocates the uplinkresources corresponding to the maximum rate to the MS 740 in step 709.In step 711, the MS transmits data to the BS 750 using the allocateduplink resources. The BS 750 periodically allocates the uplink resourcesin step 713. The MS 740 and the BS 750 repeat steps 711 and 713 untilthe data rate of the MS 740 is changed. The periodic uplink resourcesallocated by the BS have been decided in step 707.

When the MS 740 is to decrease the data rate in step 715, it transmitsdata piggybacked with a Grant Management subheader to the BS 750 in step717. The Grant Management subheader contains information indicating adecreased requested rate. The BS 750 recognizes from the GrantManagement subheader that the MS 740 is to decrease the data rate instep 719 and allocates uplink resources corresponding to the requesteddata rate to the MS 740 in step 721. In step 723, the MS 740 transmitsdata using the allocated uplink resources. In step 725, the BS 750allocates the same uplink resources for the next data. If the data rateis maintained, the MS 740 and the BS 750 repeat steps 723 and 725. Theuplink resources allocated to the MS 740 during these steps have beendecided in step 719.

When the MS 740 is to increase the data rate in step 727, it transmits acodeword requesting a bandwidth increase data to the BS 750 on the CQICHin step 729. The BS 750 increases uplink resources so as to support themaximum rate in step 731 and allocates them to the MS 740 in step 733.In step 735, the MS 740 transmits data using the allocated uplinkresources.

As described above, the present invention is directed to a method ofrequesting allocation of requested uplink resources to a BS according toa change in data rate by an MS in uplink resource scheduling for ertPSin a wireless communication system. For this purpose, the MS, whenincreasing its data rate, notifies the BS of the rate increase.

If the MS has no data to transmit and thus transitions to an off periodin ertPS for which the BS periodically allocates resources to the MS,the BS does not allocate uplink resources to the MS, thereby reducingoverhead from resource allocation. Therefore, the extra uplink resourceswhich might otherwise be allocated to the MS in the off period can beefficiently used for other purposes.

While the invention has been shown and described with reference tocertain preferred embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims.

1. A method of requesting allocation of wireless resources in a mobilestation in a wireless communication system, the method comprising:determining whether a current data rate is to be changed; if the datarate is to be changed, requesting allocation of an uplink bandwidth forthe rate changing to a base station, and receiving a changed bandwidthfrom the base station corresponding to the bandwidth allocation request.2. The method of claim 1, wherein a bandwidth is not allocated to themobile station in an initial state.
 3. The method of claim 1, whereinthe bandwidth allocation requesting step comprises transmitting apredetermined codeword over channel quality information channel (CQICH).4. The method of claim 1, wherein the bandwidth allocation requestingstep comprises transmitting a predetermined bandwidth request code. 5.The method of claim 1, wherein the mobile station uses an uplinkresource allocation scheme of extended real-time polling service(ertPS).
 6. The method of claim 1, wherein the step of receiving achanged bandwidth comprises receiving a bandwidth supporting a maximumrate determined between the mobile station and the base station duringan initial service negotiation.
 7. The method of claim 1, wherein thestep of receiving a changed bandwidth comprises receiving a bandwidthsupporting a changed data rate requested by the mobile station.
 8. Amethod of allocating wireless resources in a base station in a wirelesscommunication system, the method comprising: receiving a bandwidthallocation request for a rate changing from the mobile station; andallocating a bandwidth corresponding to the bandwidth allocation requestto the mobile station.
 9. The method of claim 8, wherein a bandwidth isnot allocated to the mobile station in an initial state.
 10. The methodof claim 8, wherein the bandwidth allocation request receiving stepcomprises receiving a predetermined codeword over channel qualityinformation channel (CQICH).
 11. The method of claim 8, wherein thebandwidth allocation request receiving step comprises receiving apredetermined bandwidth request code.
 12. The method of claim 8, whereinthe base station uses an uplink resource allocation scheme of extendedreal-time polling service (ertPS).
 13. The method of claim 8, whereinthe allocating comprises allocating a bandwidth supporting a maximumrate determined between the mobile station and the base station duringan initial service negotiation.
 14. The method of claim 8, wherein theallocation step comprises allocating a bandwidth supporting a changeddata rate requested by the mobile station.
 15. An apparatus forrequesting allocation of wireless resources in a wireless communicationsystem, comprising: a mobile station for determining whether a currentdata rate is to be increased, if a rate increase is needed, requestingallocation of an uplink bandwidth for the rate increase to a basestation, and being allocated an increased bandwidth from the basestation in correspondence with the bandwidth allocation request.
 16. Theapparatus of claim 15, wherein a bandwidth is not allocated to themobile station in an initial state.
 17. The apparatus of claim 15,wherein the mobile station transmits a predetermined codeword overchannel quality information channel (CQICH).
 18. The apparatus of claim15, wherein the mobile station transmits a predetermined bandwidthrequest code to request the allocation of the uplink bandwidth.
 19. Theapparatus of claim 15, wherein the mobile station uses an uplinkresource allocation scheme of extended real-time polling service(ertPS).
 20. The apparatus of claim 15, wherein the mobile station isallocated a bandwidth supporting a maximum rate determined between themobile station and the base station during an initial servicenegotiation.
 21. The apparatus of claim 15, wherein the mobile stationis allocated a bandwidth supporting an increased data rate requested bythe mobile station.
 22. An apparatus for allocating wireless resourcesin a wireless communication system, comprising: a base station forreceiving a bandwidth allocation request for a rate increase from amobile station, and allocating a bandwidth in correspondence with thebandwidth allocation request to the mobile station.
 23. The apparatus ofclaim 22, wherein a bandwidth is not allocated to the mobile station inan initial state.
 24. The apparatus of claim 22, wherein the basestation receives a predetermined channel quality information channel(CQICH) codeword requesting the bandwidth allocation.
 25. The apparatusof claim 22, wherein the base station receives a predetermined bandwidthrequest code requesting the bandwidth allocation.
 26. The apparatus ofclaim 22, wherein the base station uses an uplink resource allocationscheme of extended real-time polling service (ertPS).
 27. The apparatusof claim 22, wherein the base station allocates a bandwidth supporting amaximum rate determined between the mobile station and the base stationduring an initial service negotiation.
 28. The apparatus of claim 22,wherein the base station allocates a bandwidth supporting an increaseddata rate requested by the mobile station.
 29. A method of requestingallocation of uplink resources for extended real-time polling service(ertPS) in a mobile station in a wireless communication system,comprising: requesting allocation of a bandwidth by transmitting acodeword over channel quality information channel (CQICH) to a basestation, when determining that an uplink bandwidth allocation isrequired; and receiving a bandwidth supporting a maximum rate from thebase station.
 30. The method of claim 29, further comprisingtransmitting a bandwidth request code to request the allocation of anincreased bandwidth.
 31. The method of claim 29, wherein the bandwidthsupporting the maximum rate is predetermined during an initial servicenegotiation.
 32. A method of allocating uplink resources for extendedreal-time polling service (ertPS) in a base station in a wirelesscommunication system, the method comprising: receiving a channel qualityinformation channel (CQICH) codeword requesting allocation of anincreased bandwidth from a mobile station; and allocating a bandwidthsupporting a maximum rate to the mobile station.
 33. The method of claim32, further comprising the step of receiving a bandwidth request coderequesting the allocation of an increased bandwidth.
 34. The method ofclaim 32, wherein the bandwidth supporting the maximum rate ispredetermined during an initial service negotiation.
 35. An apparatusfor requesting allocation of uplink resources for extended real-timepolling service (ertPS) in a wireless communication system, comprising:a mobile station for requesting allocation of a bandwidth bytransmitting a codeword over channel quality information channel (CQICH)to a base station, when determining that an uplink bandwidth allocationis required, and receiving a bandwidth supporting a maximum rate fromthe base station.
 36. The apparatus of claim 35, wherein the mobilestation transmits a bandwidth request code to request the allocation ofan increased bandwidth.
 37. The apparatus of claim 35, wherein thebandwidth supporting the maximum rate is predetermined during an initialservice negotiation.
 38. An apparatus for allocating uplink resourcesfor extended real-time polling service (ertPS) in a wirelesscommunication system, comprising: a base station for receiving a channelquality information channel (CQICH) codeword requesting allocation of anincreased bandwidth from a mobile station, and allocating a bandwidthsupporting a maximum rate to the mobile station.
 39. The apparatus ofclaim 38, wherein the base station receives a bandwidth request coderequesting the allocation of an increased bandwidth.
 40. The apparatusof claim 38, wherein the bandwidth supporting the maximum rate ispredetermined during an initial service negotiation.